Tracheal adenoid cystic carcinoma with microscopic positive margin-how we approached with a systematic analysis review of its management

Purpose

Adenoid cystic carcinoma (ACC) of the trachea is a rare malignancy. We report a patient with ACC who underwent multimodal management including tracheal resection. A systematic review was also conducted on tracheal resection for ACC.

Methods

A literature search was conducted on MEDLINE, Embase, and PubMed using the search terms "trachea AND adenoid cystic carcinoma AND (surgery OR resection)" and articles from 2000 to August 2021 were identified. A total of 29 journal articles were included in the review.

Results

A total of 403 patients underwent surgery for tracheal ACCs. The mean age was 48.1 years and 54.7% were female. The commonest anatomical location was the lower trachea (46.9%). The mean time from symptom onset to diagnosis was 16.6 months with the commonest symptom being dyspnoea (52%). Fifty-eight percent of the patients had intraluminal growth. Tracheal resection (46.2%) and access via thoracotomy (41.4%) were the commonest procedures described. The mean length of trachea resected was 39.2 mm and the mean tumour size was 31.5 mm. 16.8% of lymph nodes were involved and 73.8% of cases had positive resection margins. The overall complication rate was 1.4-5.4% and the in-hospital mortality rate was 9.8%. The overall survival reported was 61.7% at 5 years and 54.6% at 10 years.

Conclusion

Surgical resection followed by adjuvant radiotherapy is the mainstay in the treatment of tracheal ACC, notwithstanding the high rates of involved margins. Achieving tension-free anastomosis should be the first priority given the favourable response of adjuvant therapies in reducing recurrence rate and improving overall survival.

[Fluorescence confocal microscopy-complete digitization of pathology]

BACKGROUND

Fluorescence-based confocal microscopy (FCM) can be used to create virtual H&E sections in real time. So far, FCM has been used in dermato-, uro-, and gynecopathology. FCM allows the creation of a completely digitized frozen section, which could potentially replace conventional frozen sections in the future.

OBJECTIVE

The aim of the current work is to implement FCM technology as a component of fully digitized processes in the pathological workflow. For this purpose, the current use of FCM in liver transplant pathology will be extended to other disciplines such as urology and otorhinolaryngology.

MATERIALS AND METHODS

The FCM technique continues to be used prospectively on native tissue samples from potential donor livers. Conventional frozen sections are used comparatively to virtual FCM scans.

RESULTS

The data show a nearly perfect agreement for the detection of cholangitis, fibrosis, and malignancy, and a high level of agreement for, e.g., macrovesicular steatosis, inflammation, steatohepatitis, and necrosis between virtual FCM scans and conventional routine diagnostic frozen sections.

CONCLUSION

Since the availability of time- and cost-intensive frozen section diagnostics in the context of transplant pathology in continuous operation (24/7) is now only established at very few university centers in Germany due to an increasing shortage of specialists, the use of FCM could be an important building block in the current process leading towards a fully digitized pathology workflow and should thus be extended to various disciplines.

Feasibility of intraoperative pathologic examination for sentinel lymph nodes during sentinel node navigation surgery in early gastric cancer: results of pathologic protocol for SENORITA trial

BACKGROUND

During sentinel node navigation surgery in patients with gastric cancer, intraoperative pathologic examination of sentinel nodes is crucial in determining the extent of surgery. In this study, we evaluated the feasibility and accuracy of intraoperative pathologic protocols using data from a prospective, multicenter, randomized trial.

METHODS

A retrospective analysis was conducted using data from the SEntinel Node ORIented Tailored Approach trials from 2013 to 2016. All sentinel lymph nodes were evaluated during surgery with hematoxylin-eosin (HE) staining using a representative section at the largest plane for lymph nodes. For permanent histologic evaluation, sentinel basin nodes were stained with HE and cytokeratin immunohistochemistry in formalin-fixed, paraffin-embedded (FFPE) sections and examined with HE for three deeper-step sections at 200-μm intervals. The failure rate of identification by frozen section and the metastasis rate in non-sentinel basins were investigated.

RESULTS

Of the 237 patients who underwent sentinel node basin dissection, 30 had lymph node metastases on permanent pathology. Thirteen patients had macrometastasis confirmed in frozen sections as well as FFPE sections (failure rate: 0%). Patients with negative sentinel nodes in frozen sections but micrometastasis in FFPE sections had no lymph node recurrence during the follow-up period (0%, 0/6). However, in cases with tumor-positive nodes in frozen sections, metastases in non-sentinel basins were detected in the paraffin blocks (8.3%, 2/24).

CONCLUSIONS

The single-section HE staining method is sufficient for detecting macrometastasis via intraoperative pathological examination. If a negative frozen-section result is confirmed, sentinel basin dissection can be performed safely. Otherwise, standard surgery is required.

Intraoperative frozen section of subareolar tissue in nipple-sparing mastectomy: Towards a less is more approach

BACKGROUND

Nipple preservation contributes to aesthetic outcome and quality of life in women undergoing Skin-Sparing Mastectomy (SSM) with immediate breast reconstruction for the treatment of breast cancer. Intraoperative Frozen Section (IFS) has been advocated to facilitate conversion from Nipple-Sparing Mastectomy (NSM) to SSM in cases with positive subareolar margins. This study investigated the application of IFS at our comprehensive cancer centre.

METHODS

In this single-centre retrospective study, for all patients who underwent therapeutic NSM with IFS from 2000 to 2021 pathological reports, patient- and tumour characteristics were retrieved.

RESULTS

In total 640 women were included in whom 662 intended NSMs with IFS had been performed. Sensitivity and specificity of frozen section compared with definitive histopathology were 75.2% and 98.5% respectively. In six women with a false positive result, the nipple had been removed. In 16 out of 32 women with a false negative result, the nipple was excised in a second procedure. In total 115 nipples were resected. In 40% of these nipples, no residual disease was detected.

DISCUSSION

IFS is a moderately sensitive and highly specific diagnostic tool to detect positive subareolar margins. An alternative approach is to omit frozen section but take intraoperative biopsies of the sub areolar margin, which are postoperatively analysed with definitive formalin-fixed paraffin-embedded histopathology. This allows for shared decision making regarding nipple excision in cases where minimal disease is found in subareolar tissue or cases with an indication for post-mastectomy radiotherapy.

Can We Do Breast-Conserving Surgery Without Intraoperative Frozen Section of Margin?

PURPOSE

This study was a retrospective and nonrandomized study to assess the safety and reliability of identifying the surgical margin in breast cancer breast-conserving surgery (BCS) by using intraoperative ultrasonic location and specimen mammography instead of traditional intraoperative frozen pathological section.

METHODS

Among the patients who underwent BCS from May 2019 to October 2021, according to the different methods of evaluating the intraoperative margin, 104 breast cancer patients were included in the frozen edge group, 53 breast cancer patients were included in the freeze-free group, and the surgeon judged whether extended resection was needed based on the results of pathological section or evaluation of intraoperative ultrasound and mammography. The surgical margins of the two groups were judged by postoperative pathological results as the gold standard.

RESULTS

The median waiting pathology results time in the frozen edge group was 64 minutes, while the waiting time in the freeze-free group was 30 minutes, and the difference was statistically significant (P < .0001). The postoperative pathological results showed that the positive rate of the surgical margin in the frozen edge group was 0.96%. The coincidence rate of intraoperative frozen and postoperative pathological results was 99.04%. The coincidence rate between intraoperative mammography and postoperative pathological results was 100%.

CONCLUSIONS

In BCS, the method of using intraoperative staining markers combined with mammography to evaluate the resection margin is highly accurate, reliable, economical and convenient, and at the same time reduces the waiting time of the operator during the operation. However, this was not a randomized controlled study, and there was patient selection bias, and its safety needs to be confirmed by long-term follow-up. In the future, it is expected to become the mainstream means of evaluating.

Intraoperative pathologic diagnosis of central nervous system lymphomas: A comparison of frozen and permanent section diagnoses, and the significance of preoperative imaging

BACKGROUND

Central nervous system (CNS) lymphomas, either primary or secondary in origin, are rare malignant tumors affecting the brain, spinal cord, or leptomeninges. Diagnosis of CNS lymphomas is complicated by their diverse clinical presentations, radiological features, and histopathological characteristics. Although frozen section (FS) analysis is commonly employed for various CNS tumors, its role and accuracy in CNS lymphoma diagnosis are less explored. In this study, we conducted a comparative analysis to assess the impact of knowledge of preoperative imaging on enhancing the accuracy of FS diagnosis in CNS lymphomas.

METHODS

Data collection involved a retrospective review of CNS lymphoma patients from January 2009 to August 2021. Patients who underwent intraoperative consultation were included, excluding those with prior cortisone treatment. The dataset incorporated patient demographics, classification as primary or secondary lymphoma, radiological preliminary diagnoses, FS diagnosis, and permanent section diagnosis. We employed various archived materials, including FSs, touch imprint slides, crush cytology slides, H&E-stained sections, and immunohistochemical stains, and re-evaluated all slides for diagnostic validation.

RESULTS

Our study included 25 patients, of whom 60 % were female and had a mean age of 56.5 years. Preoperative radiology data were available for 80 % of cases, with preliminary diagnoses commonly including lymphoma and/or metastasis. Intraoperative consultation results indicated lymphoma in 18 (72 %) patients, with discordance observed in 28 % of cases when compared to permanent section diagnoses. Most permanent section diagnoses were diffuse large B-cell lymphomas (92 %), with the remainder being T-cell non-Hodgkin lymphoma (4 %) and follicular lymphoma (4 %). Intraoperative misdiagnoses were significantly associated with the absence of knowledge of preoperative imaging.

CONCLUSION

Our study demonstrates the reliability of FS diagnosis for CNS lymphomas during surgery, with a favorable complete concordance rate of 72 % when compared to permanent diagnoses. Importantly, lack of knowledge of preoperative imaging significantly impaired diagnostic accuracy in FS, emphasizing the need for close collaboration between pathologists and radiologists.

Immunocytochemistry on frozen-embedded cell block for the diagnosis of hematolymphoid cytology specimen: a straightforward alternative to the conventional cell block

Agarose-based cell block (CB) technique can be modified to be combined with the frozen section technique for the preparation of a high-quality frozen-embedded CB (F-CB) from an effusion or fine-needle aspiration (FNA) cytology sample. This combined technique can be effectively used for the immunocharacterization of the hematolymphoid cells on F-CB. To demonstrate the applicability of performing diagnostic ICC on F-CB, we have analyzed the immunophenotype of the hematolymphoid cells in a series of eight cases of effusions and eight cases of FNA cytology specimens by using CB-ICC on sections cut from frozen-embedded CBs. The SurePathTM residue or cytologic material scraped off from the FNA cytology smear that was diagnostic for or suspicious of hematolymphoid malignancy was pelleted and pre-embedded in agarose. Half of the agarose-embedded pellet was frozen-embedded in OCT compound for the preparation of F-CB, while the other half was processed for the preparation of paraffin-embedded CB. Sections cut from the F-CB and P-CB were used for CB-ICC. Panels of ICC on the F-CBs could enable the immunocytochemical differential diagnosis of large cell hematologic malignancies that encompass anaplastic large cell lymphoma and other forms of large-cell hematolymphoid malignancies such as large B-cell lymphomas, anaplastic plasma cell myeloma, myeloid sarcoma, and T-lymphoblastic lymphoma. It also appeared that the small B-cell lymphomas in the effusions or FNAs could be differentially diagnosed with the aid of CB-ICC on the F-CB. A modified agarose-based CB technique can be combined with the frozen-embedded CB method for the preparation of F-CB that can be directly used for the immunocytochemical differential diagnosis of hematolymphoid cytology samples.

A biosensor for D-2-hydroxyglutarate in frozen sections and intraoperative assessment of IDH mutation status

The oncometabolite D-2-hydroxyglutarate (D-2-HG) has emerged as a valuable biomarker in tumors with isocitrate dehydrogenase (IDH) mutations. Efficient detection methods are required and rapid intraoperative determination of D-2-HG remains a huge challenge. Herein, D-2-HG dehydrogenase from Achromobacter xylosoxidans (AX-D2HGDH) was found to have high substrate specificity. AX-D2HGDH dehydrogenizes D-2-HG and reduces flavin adenine dinucleotide (FAD) bound to the enzyme. Interestingly, the dye resazurin can be taken as another substrate to restore FAD. AX-D2HGDH thus catalyzes a bisubstrate and biproduct reaction: the dehydrogenation of D-2-HG to 2-ketoglutarate and simultaneous reduction of non-fluorescent resazurin to highly fluorescent resorufin. According to steady-state analysis, a ping-pong bi-bi mechanism has been concluded. The Km values for resazurin and D-2-HG were determined as 0.56 μM and 10.93 μM, respectively, suggesting high affinity to both substrates. On the basis, taking AX-D2HGDH and resazurin as recognition and fluorescence transducing element, a D-2-HG biosensor (HGAXR) has been constructed. HGAXR exhibits high sensitivity, accuracy and specificity for D-2-HG in different biological samples. With the aid of HGAXR and the matched low-cost palm-size detecting device, D-2-HG levels in frozen sections of resected brain tumor tissues can be measured in a direct, simple and accurate manner with a fast detection (1-3 min). As the technique of frozen section is familiar to surgeons and pathologists, HGAXR and the portable device can be easily integrated into the current workflow, having potential to provide rapid intraoperative pathology for IDH mutation status and guide decision-making during surgery.

[Histopathologic diagnosis of solid and cystic pancreatic lesions with a focus on ductal adenocarcinoma : A vademecum for daily practice]

Pancreas pathology is constantly evolving and can present various challenges for pathologists. This paper is focused on providing helpful hints for daily routine diagnostics. During histopathological analysis of pancreas biopsies, pancreatic ductal adenocarcinoma must be distinguished not only from other solid neoplasms, but especially from its mimicker, autoimmune pancreatitis. This can be achieved by a systematic workup following clear diagnostic criteria. When analyzing samples from cystic pancreatic lesions, mucin-producing neoplasms must be detected due to their role as pancreatic cancer precursors; molecular analyses can help considerably with their detection and distinction. During frozen section examination, evaluation of the pancreatic neck margin and analysis of unclear lesions of the liver are two important tasks, which are explained further in this article. A special challenge is the evaluation of neoadjuvant treated pancreatic cancer, which requires a detailed macroscopic and microscopic workup. Finally, current advances in precision oncology and emerging approaches for pancreatic cancer within this field are discussed. With the advancement of technical possibilities and their increasingly broad implementation, the classification systems in pancreatic pathology will continue to gain in complexity, but also in accuracy.

Diagnostic accuracy of intraoperative frozen section for margin evaluation of oral cavity squamous cell carcinoma

OBJECTIVES

Intraoperative frozen-section evaluation is a valuable technique for detecting positive margins intraoperatively for oral squamous cell carcinoma. We conducted this study to determine the diagnostic accuracy of frozen section in detecting margin status and the effect of tumor grade and stage on diagnostic accuracy.

RESULTS

A total of 251 biopsy-proven cases of oral squamous cell carcinoma were included in this study. The tissue specimen resected during surgery was sent to the laboratory for frozen section evaluation. The frozen section results were then compared with the permanent section results to determine the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy. The mean age of the patients included in the study was 51.65 ± 10.03 years, with male predominance (55.4%). The overall sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of frozen section were 88.81%, 94.84%, 95.20%, 88.10%, and 91.63%, respectively. We conclude that frozen section is a useful technique in determining the margin status intraoperatively in oral cancers, with high diagnostic accuracy. Moreover, certain clinical parameters such as age, gender, disease duration, and tumor stage and grade appear to affect the diagnostic accuracy of frozen section.

Primary Non-Function of Hepatic Allograft With Preexisting Microvesicular Steatosis/Foamy Degeneration and Mild Large-Droplet Macrovesicular Steatosis

It has been established that more than mild large-droplet macrovesicular steatosis (LD-MAS) is associated with increased risk of graft non-function. In contrast, even severe small-droplet macrovesicular steatosis (SD-MAS) has been found to be less prognostically significant. It remains unclear if a donor liver with diffuse microvesicular steatosis is associated with an increased risk of graft dysfunction. A 56-year-old male with alcoholic cirrhosis was transplanted with a liver from a 42-year-old overweight male donor after brain death. The frozen section of the donor liver biopsy taken at harvest showed diffusely enlarged clear/foamy hepatocytes and mild LD-MAS (about 5-10% of total tissue). The reperfusion liver biopsy taken at time 0 of transplantation showed hemorrhage, pale and enlarged hepatocytes, and mild LD-MAS (about 10% of total tissue) with lipopeliosis. The graft became non-functional, and the patient was re-transplanted 24 h after the initial transplantation. Histologic examination of the failed liver allograft showed extensive hemorrhagic necrosis, neutrophilic inflammation, diffuse microvesicular steatosis, and large extracellular fat droplets (about 20% of total tissue). This case demonstrates that precautions are needed to avoid using livers with diffuse and severe microvesicular steatosis.

Analysis of false reasons based on the artificial intelligence RRCART model to identify frozen sections of lymph nodes in breast cancer

BACKGROUND

Breast cancer is the most common malignant tumor in the world. Intraoperative frozen section of sentinel lymph nodes is an important basis for determining whether axillary lymph node dissection is required for breast cancer surgery. We propose an RRCART model based on a deep-learning network to identify metastases in 2362 frozen sections and count the wrongly identified sections and the associated reasons. The purpose is to summarize the factors that affect the accuracy of the artificial intelligence model and propose corresponding solutions.

METHODS

We took the pathological diagnosis of senior pathologists as the gold standard and identified errors. The pathologists and artificial intelligence engineers jointly read the images and heatmaps to determine the locations of the identified errors on sections, and the pathologists found the reasons (false reasons) for the errors. Through NVivo 12 Plus, qualitative analysis of word frequency analysis and nodal analysis was performed on the error reasons, and the top-down error reason framework of "artificial intelligence RRCART model to identify frozen sections of breast cancer lymph nodes" was constructed based on the importance of false reasons.

RESULTS

There were 101 incorrectly identified sections in 2362 slides, including 42 false negatives and 59 false positives. Through NVivo 12 Plus software, the error causes were node-coded, and finally, 2 parent nodes (high-frequency error, low-frequency error) and 5 child nodes (section quality, normal lymph node structure, secondary reaction of lymph nodes, micrometastasis, and special growth pattern of tumor) were obtained; among them, the error of highest frequency was that caused by normal lymph node structure, with a total of 45 cases (44.55%), followed by micrometastasis, which occurred in 30 cases (29.70%).

CONCLUSIONS

The causes of identification errors in examination of sentinel lymph node frozen sections by artificial intelligence are, in descending order of influence, normal lymph node structure, micrometastases, section quality, special tumor growth patterns and secondary lymph node reactions. In this study, by constructing an artificial intelligence model to identify the error causes of frozen sections of lymph nodes in breast cancer and by analyzing the model in detail, we found that poor quality of slices was the preproblem of many identification errors, which can lead to other errors, such as unclear recognition of lymph node structure by computer. Therefore, we believe that the process of artificial intelligence pathological diagnosis should be optimized, and the quality control of the pathological sections included in the artificial intelligence reading should be carried out first to exclude the influence of poor section quality on the computer model. For cases of micrometastasis, we suggest that by differentiating slices into high- and low-confidence groups, low-confidence micrometastatic slices can be separated for manual identification. The normal lymph node structure can be improved by adding samples and training the model in a targeted manner.

Reconsidering the Role of Frozen Section in Sentinel Lymph Node Biopsy for Mastectomy Patients

INTRODUCTION

Axillary lymph node dissection was recommended for mastectomy patients with more than two nodal metastases from sentinel lymph node biopsy. Conventionally, intraoperative frozen section was sent routinely to reduce the need for second-stage axillary lymph node dissection; however, recent global trend has seen decreasing usage of the intraoperative analyses. This pilot study conducted in Thailand aimed to evaluate the role of intraoperative frozen section of sentinel lymph node biopsy in early-stage breast cancer patients who underwent mastectomy.

METHODS

A 5-y retrospective study of 1773 patients was conducted in Thailand. The inclusion criteria were early-stage breast cancer patients with either radiologically negative nodes, or radiographically borderline nodes found to be negative on fine needle aspiration who underwent mastectomy and sentinel lymph node biopsy. Reoperations were indicated when three or more nodal metastases were detected on the pathological analysis. The reoperation rate prevented by frozen section and the reoperation rate needed for those with permanent section alone were reported.

RESULTS

Among 265 patients, 202 patients underwent concomitant intraoperative frozen section while the remaining 63 patients underwent permanent section alone. Six patients (3.0%) from the frozen section group and one patient (1.6%) from the permanent section group were found with more than two nodal metastases. Despite using intraoperative frozen sections, only one patient from each group required reoperation. There was no significant difference in the number of patients requiring reoperation between the frozen section group and the permanent section group.

CONCLUSIONS

Our study provides strong evidence to all surgeons that in early breast cancer patients undergoing mastectomy, sentinel lymph node biopsy with permanent section analysis alone may not lower the standard of care compared to using additional intraoperative frozen section analysis. Adopting this practice may lead to decreased operation costs, operative time, and anesthetic side effects.

Neurosarcoidosis: Frozen section rescue for a big mimicker - A case report

Neurosarcoidosis is an uncommon but potentially serious manifestation of sarcoidosis. Diagnosis may be particularly challenging especially when neurosarcoidosis occurs in isolation or is the initial presentation of the systemic disease. The authors take this opportunity to report a case of neurosarcoidosis, presenting as the first manifestation of the disease, diagnosed on frozen section, occurring in a 43-year-old male patient with no past history or manifestation of sarcoidosis.

Ocular Crystal-Storing Histiocytosis with Co-existing MALT Lymphoma-A Rare Case with Cytologic and Heretofore Not Reported Findings on Frozen Section

BACKGROUND

Crystal-storing histiocytosis (CSH) is a rare disorder which most commonly occurs in the setting of concurrent lymphoproliferative disease. Morphologically, it consists of aggregates of histiocytes containing eosinophilic crystalline material, which in most cases is composed of aggregated abnormal light chains.

METHODS

Using histomorphology, immunohistochemistry and in situ hybridization, the authors characterize a rare case of orbital CSH associated with extranodal marginal zone (MALT) lymphoma and report for the first time the frozen section features of CSH.

RESULTS

The frozen section featured plump histiocytes with ample weakly basophilic to grayish cytoplasm with a microvacuolated appearance and focal stippling. These features stand in contrast with the formalin-fixed, paraffin embedded histomorphological appearance of aggregates of plump histiocytes with densely eosinophilic crystalline cytoplasmic material.

CONCLUSION

CSH is a challenging diagnosis to make on frozen section. The artifacts that preclude its recognition, as well as differential diagnoses of this entity in the head and neck are discussed.

Intraoperative assessment of axillary sentinel lymph nodes by telepathology

PURPOSE

Although axillary dissection is no longer indicated for many breast cancer patients with 1-2 positive axillary sentinel lymph nodes (ASLN), intraoperative ASLN assessment is still performed in many institutions for patients undergoing mastectomy or neoadjuvant therapy. With recent advancements in digital pathology, pathologists increasingly evaluate ASLN via remote telepathology. We aimed to compare the performance characteristics of remote telepathology and conventional on-site intraoperative ASLN assessment.

METHODS

Data from ASLN evaluation for breast cancer patients performed at two sites between April 2021 and October 2022 was collated. Remote telepathology consultation was conducted via the Aperio eSlideManager system.

RESULTS

A total of 385 patients were identified during the study period (83 telepathology, 302 on-site evaluations). Although not statistically significant (P = 0.20), the overall discrepancy rate between intraoperative and final diagnoses was slightly higher at 9.6% (8/83) for telepathology compared with 5.3% (16/302) for on-site assessment. Further comparison of performance characteristics of ASLN assessment between telepathology and conventional on-site evaluation revealed no statistically significant differences between deferral rates, discrepancy rates, interpretive or sampling errors, major or minor disagreements, false negative or false positive results as well as clinical impact and turn-around time (P ≥ 0.12).

CONCLUSION

ASLN assessment via telepathology is not significantly different from conventional on-site evaluation, although it shows a slightly higher overall discrepancy rate between intraoperative and final diagnoses (9.6% vs. 5.3%). Further studies are warranted to ensure accuracy of ASLN assessment via telepathology.

Confounders of intraoperative frozen section pathology during glioma surgery

Although frozen section pathology (FSP) is commonly performed during surgery for glioma-suspicious lesions, confounders of accuracy are largely unknown. FSP and final diagnosis were compared in 398 surgeries for glioma-suspicious lesions. Diagnostic accuracy, risk factors for diagnostic shift from neoplastic to non-neoplastic tissue and vice versa according to the final diagnosis, and the impact on intraoperative and postoperative decision-making were analyzed. Diagnostic shift occurred in 70 cases (18%), and sensitivity, specificity, and the positive (PPV) and negative (NPV) predictive value of FSP were 82.5%, 77.8%, 99.4%, and 9.3%, respectively. No correlations between shift and patients' age and sex, sample fluorescence or volume, tumor location, correct information on the pathology form, final high- or low-grade histology, or molecular alterations were found (p > .05, each). Shift was more common after irradiation (25% vs 15%; p = .025) or chemotherapy (26% vs 15%; p = .022) than in treatment naïve cases and correlated with the type of surgery (p = .002). FSP altered intraoperative decision-making in 25 cases (6%). Postoperative shift led to repeated surgery in 12 patients (3%). In 45 cases, in which FSP and final diagnosis based on the same tissue, shift occurred in only 5 patients (11%), and sensitivity, specificity, PPV, and NPV for FSP were 77.4%, 78.6%, 88.9%, and 61.1%, respectively. No correlations between diagnostic shift and any of the analyzed variables were found (p > .05, each). Although accuracy of FSP during glioma surgery is sufficient, moderate NPV should be considered during intraoperative decision-making. While confounders are sparse, accuracy might be increased by repeated sampling. Diagnostic shift rarely alters postoperative treatment strategy.

Accuracy of Intraoperative Frozen Section Analysis of Lymph Nodes in Women Undergoing Axillary Sampling for Treatment of Breast Cancer: Single Institution Audit

BACKGROUND

Axillary lymph node (LN) positivity is an important prognostic factor in breast cancer. Almost 30% clinically node negative (cN0) early breast cancers have positive nodes on pathology, wherein an axillary dissection is done as a second stage surgery. Intra operative frozen section (FS) potentially avoids redo surgery.

MATERIALS AND METHODS

We performed a retrospective audit for the false negative rate of intraoperative FS, from 2014 to 2018. All cN0 women undergoing upfront surgery, who underwent low axillary sampling (LAS) with FS were included.

RESULTS

Of 22,854 breast cancer cases, 2230 underwent LAS, of which 877 were node positive. Intraoperative FS was negative in 1423/2230 (63.81%) cases, of which 71/1423 (4.98%) were false negative, and came positive on final histopathology report (HPR). These 71 women had a median of 5 nodes (mean 4.85) dissected on FS (range 1-12) with a median 1 (mean 1.3) node positive (range 1-6) on HPR. The sensitivity of FS was 91.89% (95% CI, 89.89-93.62), with a negative predictive value of 95.01% (95% CI, 93.84-95.97), accuracy of 96.73% (95% CI, 95.90-97.43) and false negative rate 4.98%. On logistic regression analysis, micrometastasis (Odds ratio (OR) 7.76, 95% CI, 3.49-17.25, P < .001) lobular histology (OR 2.50, 95% CI, 1.007-6.223, P = .04) and nodes dissected (OR 1.18, 95% CI, 1.07-1.30, P = .001) were associated with higher false negative FS, and extra nodal extension (OR 0.32, 95% CI, 0.18-0.57, P ≤ .001) with lower false negative FS.

CONCLUSION

The high concordance between intraoperative FS and definitive histology, suggests it's routine use for Sentinel lymph node/LAS LN can help avoid a second surgery.

Diagnostic accuracy of sentinel lymph node frozen section analysis in patients with early-stage cervical cancer: A systematic review and meta-analysis

OBJECTIVE

To assess the diagnostic accuracy of intraoperative SLN frozen section analysis compared with ultrastaging in patients with early-stage cervical cancer.

METHODS

A systematic literature review was conducted following the PRISMA checklist. MEDLINE (via Ovid), Embase, and the Cochrane Central Register of Controlled Trials were searched from inception until February 2023. The inclusion criteria were patients with early-stage cervical cancer (2018 FIGO stage I-II), consisting of the histological subtype squamous cell carcinoma, adenocarcinoma, or adenosquamous carcinoma (≥90% of the patients in each study), who underwent SLN detection (with any tracer) and intraoperative frozen section followed by SLN ultrastaging. Randomized controlled trials, prospective and retrospective observational studies were considered. The detection rates and measures of diagnostic accuracy were pooled using a random effects univariate model. A preplanned subgroup meta-analysis was conducted, with isolated tumor cells excluded as positive lymph nodes. The review was registered in PROSPERO (CRD42023397147).

RESULTS

The search identified 190 articles, with 153 studies considered potentially eligible after removing duplicates. Fourteen studies met the selection criteria, including a total of 1720 patients. Seven studies were retrospective, and the other seven were prospective. Frozen section analysis detected 159 of 292 (54.5%) patients with lymph node metastases. In 281 patients the type of volume metastasis was reported: 1 of 41 (2.4%) patients had isolated tumor cells, 21 of 78 (26.9%) patients had micrometastases, and 133 of 162 (82.1%) patients had macrometastases. The pooled sensitivity of intraoperative SLN frozen section analysis was 65% (95% CI, 51-77%) for macrometastases, micrometastases, and isolated tumor cells. When we excluded patients with isolated tumor cells, the pooled sensitivity increased to 72% (95% CI, 60-82%).

CONCLUSION

SLN frozen section detects 65% of lymph node metastases compared with SLN ultrastaging and may prevent unnecessary radical surgery in some patients with early-stage cervical cancer.

Accuracy of Frozen Section and Clinical/Radiological Diagnosis with Final Histopathology of Pelvic Masses in a Teaching Institute with a Non-oncology Setup, in Northeast India

Background

Frozen section (FS) is an important decision making intraoperative tool in a non-oncology center especially in a region where women are often "lost to followup".

Objectives

Evaluate the use of FS in non-oncology setup for ovarian and uterine masses.

Methods

A retrospective analysis of women who had undergone surgery with frozen section for large abdominopelvic masses at Central Referral Hospital, Sikkim, India, from July 2017 to July 2021.

Results

22 women were taken into study out of which 18 had FS for ovarian masses while 4 had frozen section for large uterine masses. All ovarian masses looked malignant on imaging while only 7 looked malignant intraoperatively. FS detected 8 women (44%) with ovarian malignancy out of which 2 were suspicious. The 2 suspicious cases were benign on final histopathology. FS was negative for malignancy in 10 women (56%) out of which 2 were borderline sero-mucinous on final histopathology. FS for ovarian masses showed sensitivity: 66.7% specificity: 83.3%, NPV: 83.3% and Accuracy of 80% when compared to the final histopathology. Intraoperatively 3 out of 4 uterine masses looked malignant. However, all of the uterine masses were negative on FS and final histopathology.

Conclusion

Non-oncology centers are burdened with variety of benign surgeries, hence, FS is effective in detecting malignancy in ovarian tumors but not so in large uterine masses. Performing FS prevents "lost to follow ups" in ovarian tumors while avoiding it, saves time of experts while dealing with large uterine masses.

Histopathology of Ganglion Cells in the Proximal Resected Bowel Correlates With the Clinical Outcome in Hirschsprung Disease: A Pilot Study

INTRODUCTION

Intraoperative leveling biopsy by identifying ganglion cells is crucial to determine surgical margin during surgery for Hirschsprung disease (HSCR). The anastomosis should be performed at least 5 cm proximal to the ganglionic segment to prevent transition zone pull-through. However, the length of the transition zone could be much longer than expected and the histological evaluation of the entire circumference of the proximal margin is recommended, which is time-consuming and not applicable for leveling biopsy. We found that the histopathologic features of ganglion cells varied in the examined bowel specimens and demonstrated a pattern similar to immature and degenerated neuron cells. We assumed that the histopathologic features of ganglion cells in the proximal resected bowel were associated with the clinical outcome and might guide the leveling biopsy. In this study, we described a histopathologic grade of ganglion cells based on the degree of maturity and degeneration. We assessed the correlation between the histopathological grade of ganglion cells in the proximal surgical margin and clinical outcome.

METHODS

Three hundred fifty seven patients with HSCR treated between 2013 and 2020 were included. The ganglion cells were divided into six grades based on the histopathologic features in frozen sections. Medical records and detailed histopathologic results of intraoperative frozen sections were reviewed. Follow-up data were collected to evaluate clinical outcomes. The pediatric incontinence and constipation scoring system was used to predict bowel function.

RESULTS

The histopathologic results of proximal resected bowel from 357 HSCR patients were presented as follows: Grade I in 52 patients (14.6%), Grade II in 186 patients (52.1%), Grade III in 107 patients (30.0%), and Grade IV in 12 patients (3.4%). The median follow-up time was 46.8 mo (13.0-97.6 mo). The histopathologic grade of ganglion cells from the proximal resected margin was significantly related to postoperative constipation problems and the incidence of Hirschsprung-associated enterocolitis. The results from the pediatric incontinence and constipation scoring system indicated a positive correlation between better postoperative bowel function and lower histopathologic grade of ganglion cells.

CONCLUSIONS

This pilot study showed an association between the histopathologic features of ganglion cells in the proximal surgical margin and the clinical outcome. It may provide additional information for intraoperative pathologic consultation in leveling biopsy to prevent insufficient resection of the affected colon. A prospective study is warranted to validate these findings before clinical application.

Patterns of Major Frozen Section Interpretation Error: An In-Depth Analysis From a Complex Academic Surgical Pathology Practice

OBJECTIVES

To establish baseline error rates due to misinterpretation and to identify scenarios in which major errors were most common and potentially preventable.

METHODS

Our database was queried over a 3-year period for major discrepancies due to misinterpretation. These were stratified by histomorphologic setting, service, availability/type of prior material, and years of experience and subspecialization of the interpreting pathologist.

RESULTS

The overall discordance rate between frozen section (FS) and final diagnoses was 2.9% (199/6,910). Seventy-two errors were due to interpretation, of which 34 (47.2%) were major. Major error rates were highest on the gastrointestinal and thoracic services. Of major discrepancies, 82.4% were rendered in subdisciplines outside those of the FS pathologist. Pathologists with fewer than 10 years' experience made more errors than those with more experience (55.9% vs 23.5%, P = .006). Major error rates were greater for cases without previous material compared to those with a prior glass slide (47.1% vs 17.6%, P = .009). Common histomorphologic scenarios in which disagreements were made involved discriminating mesothelial cells from carcinoma (20.6%) and accurately recognizing squamous carcinoma/severe dysplasia (17.6%).

CONCLUSIONS

To improve performance and decrease future misdiagnoses, monitoring discordances should be a continuous component of surgical pathology quality assurance programs.

Utility of intraoperative pathology consultations of whipple resection specimens and their impact on final margin status

The resection margin status is a significant surgical prognostic factor for the long-term outcomes of patients undergoing pancreaticoduodenectomy (Whipple procedure). As a result, surgeons frequently rely on intraoperative consults (IOCs) involving frozen sections to evaluate margin clearance during these resections. Nevertheless, the impact of this practice on final margin status and long-term outcomes remains a topic of debate. This study aimed to assess the impact of IOCs on the clearance rate of resection margins following Whipple procedure and distal pancreatectomy. A retrospective database review of all patients who underwent Whipple procedure or distal pancreatectomy at our institution between 2018 and 2020 was performed to evaluate the utility of IOCs by gastrointestinal surgeons and its correlation with final postoperative surgical margin status. A significant variation in the frequency of IOC requests for margins among surgeons was noted. However, the use of frozen section analysis for intraoperative margin assessment was not significantly associated with the clearance rate of final post-operative margins. More frequent use of IOC did not result in higher final margin clearance rate, an important prognostic factor following Whipple procedure.

Diagnostic accuracy of frozen section biopsy for early gastric cancer extent during endoscopic submucosal dissection: a prospective study

BACKGROUND

Accurate diagnosis of the lateral extent of early gastric cancer during endoscopic submucosal dissection (ESD) is crucial to achieve negative resection margins. Similar to intraoperative consultation with a frozen section in surgery, rapid frozen section diagnosis with endoscopic forceps biopsy may be useful in assessing tumor margins during ESD. This study aimed to evaluate the diagnostic accuracy of frozen section biopsy.

METHODS

We prospectively enrolled 32 patients undergoing ESD for early gastric cancer. Biopsy samples for the frozen sections were randomly collected from fresh resected ESD specimens before formalin fixation. Two different pathologists independently diagnosed 130 frozen sections as "neoplasia," "negative for neoplasia," or "indefinite for neoplasia," and the frozen section diagnosis was compared with the final pathological results of the ESD specimens.

RESULTS

Among the 130 frozen sections, 35 were from cancerous areas, and 95 were from non-cancerous areas. The diagnostic accuracies of the frozen section biopsies by the two pathologists were 98.5 and 94.6%, respectively. Cohen's kappa coefficient of diagnoses by the two pathologists was 0.851 (95% confidence interval: 0.837-0.864). Incorrect diagnoses resulted from freezing artifacts, a small volume of tissue, inflammation, the presence of well-differentiated adenocarcinoma with mild nuclear atypia, and/or tissue damage during ESD.

CONCLUSIONS

Pathological diagnosis of frozen section biopsy is reliable and can be applied as a rapid frozen section diagnosis for evaluating the lateral margins of early gastric cancer during ESD.

Usefulness and limitations of intraoperative pathological diagnosis using frozen sections for spinal cord tumors

BACKGROUND

Intraoperative pathological diagnosis has a major influence on the intra- and postoperative management of spinal cord tumors. Thus, the aim of this study was to assess the reliability of intraoperative pathological diagnosis for spinal cord lesions by comparing it with the final pathological diagnosis and to determine its usefulness and limitations.

METHOD

Three-hundred and three consecutive patients (mean age, 53.9 years) with neoplastic spinal cord lesions who underwent initial surgery between 2000 and 2021 were included. The anatomical locations of the spinal cord tumors and the implementation rate of intraoperative pathological diagnosis in each tumor type were evaluated. As the primary outcome, we determined the concordance rates between the intraoperative pathological diagnosis and the final diagnosis. When the intraoperative pathological diagnosis and final diagnosis were the same, the diagnosis was defined as a "match." Otherwise, the diagnosis was defined as a "mismatch."

RESULTS

The overall implementation rate of intraoperative pathological diagnosis was 53%, with implementation rates of 71%, 45%, 47%, and 50% for intramedullary, intradural extramedullary, extradural, and dumbbell tumors, respectively. The overall concordance rate was 87.6%, with concordance rates of 80%, 95%, 75%, and 90% for intramedullary, intradural extramedullary, extradural, and dumbbell tumors, respectively (p < 0.05). The diagnoses of ependymomas, low-grade astrocytomas, and high-grade astrocytomas was occasionally difficult among intramedullary tumors. Among intradural extramedullary tumors, differentiation between grade 1 meningioma and high-grade meningioma was difficult using intraoperative pathological diagnosis.

CONCLUSIONS

Surgeons must recognize the lower accuracy of intraoperative pathological diagnosis for intramedullary and extradural lesions and make a final decision by considering the intraoperative gross findings, preoperative clinical course, and imaging.

Intraoperative Pathological Evaluation of Suspicious Peritoneal Nodules for Surgical Decision-making in Gastric Cancer

BACKGROUND

When frozen pathological results of suspicious peritoneal nodules found in gastric cancer (GC) patients are negative or indeterminant, whether to perform gastrectomy will always be a dilemma for surgeons. This study aimed to facilitate intraoperative surgical decision-making based on frozen section (FS) results and clinicopathological characteristics.

METHODS

From January 2015 to July 2021, 318 GC patients were enrolled retrospectively. The correlations between frozen and paraffin pathology of peritoneal nodules were examined. Then, predictive factors of positive paraffin section (PS) results were identified, and a nomogram was constructed. The survival significance of gastrectomy was also explored.

RESULTS

Of 70 FS-negative patients, 59 (84.3%) had concordant negative PS results, while the PS results of 11 (15.7%) were positive. Forty-six (93.9%) and 3 (6.1%) of 49 patients with indeterminant FS results had positive and negative PS results, respectively. The PS results of 95 FS-positive patients were all positive. A nomogram for predicting positive PS results was developed based on Lauren type, nodule distribution, and CA125. Gastrectomy for FS-negative patients improved survival compared to no gastrectomy (HR 0.26, 95% CI 0.11-0.62; P = 0.0012). Survival benefits for gastrectomy vs. no gastrectomy were not demonstrated in patients with indeterminant (HR 0.74, 95% CI 0.27-2.01; P = 0.53) and positive (HR 0.87, 95% CI 0.43-1.74; P = 0.69) FS results.

CONCLUSIONS

Gastrectomy can be justified for the treatment of operable GC patients with negative frozen pathological results of peritoneal nodules. For patients with positive and indeterminant frozen pathological results, gastrectomy is not recommended unless it is performed as palliative surgery.

The impact of intraoperative frozen section in patients with clinically node-negative breast cancer (cN0/ycN0) who received neoadjuvant systemic therapy

BACKGROUND

When surgical axillary staging reveals residual metastatic deposits in breast cancer (BC) patients who had received neoadjuvant chemotherapy (NACT), axillary lymphonodectomy is indicated. In this study, we investigate whether it is reasonable to perform intraoperative frozen section (FS) of the removed sentinel lymph nodes (SLNs) in cases where NACT had been administered in patients who had a clinically negative nodal status at the time of diagnosis.

PATIENTS AND METHODS

We analyzed data from 101 BCE patients with 103 carcinomas who were diagnosed between 2014 and 2021 and met the above-mentioned criteria.

RESULTS

In three cases (2.8% of the study group), histologically active tumor tissue was detected in the removed axillary LNs. Discontinuation of therapy/the use of a low-dose NACT regimen was a significant factor for positive LNs (p = 0.02) at the subsequent surgical procedure; tumor progression during therapy approached borderline significance (p = 0.058). Among patients who had completed NACT with the planned standard dose regimen, and in which the primary tumors showed a response to therapy (n = 94), only one case had histologically detected residual metastases in the SLNs.

CONCLUSIONS

Certified breast centers aim to improve the outcome of the patients. However, these specialized centers should also focus on economic aspects. This means that diagnostic and therapeutic procedures should be continuously critically reviewed in order to avoid unnecessary expenses. In BC patients with clinically node negative disease who completed NACT as planned and in which the tumor showed a good response to therapy, time consuming and costly FS of the SLNs removed should be omitted.

Invasiveness assessment by artificial intelligence against intraoperative frozen section for pulmonary nodules ≤ 3 cm

PURPOSE

To investigate the performance of an artificial intelligence (AI) algorithm for assessing the malignancy and invasiveness of pulmonary nodules in a multicenter cohort.

METHODS

A previously developed deep learning system based on a 3D convolutional neural network was used to predict tumor malignancy and invasiveness. Dataset of pulmonary nodules no more than 3 cm was integrated with CT images and pathologic information. Receiver operating characteristic curve analysis was used to evaluate the performance of the system.

RESULTS

A total of 466 resected pulmonary nodules were included in this study. The areas under the curves (AUCs) of the deep learning system in the prediction of malignancy as compared with pathological reports were 0.80, 0.80, and 0.75 for all, subcentimeter, and solid nodules, respectively. Additionally, the AUC in the AI-assisted prediction of invasive adenocarcinoma (IA) among subsolid lesions (n = 184) was 0.88. Most malignancies that were misdiagnosed by the AI system as benign diseases with a diameter measuring greater than 1 cm (26/250, 10.4%) presented as solid nodules (19/26, 73.1%) on CT. In an exploratory analysis involving nodules underwent intraoperative pathologic examination, the concordance rate in identifying IA between the AI model and frozen section examination was 0.69, with a sensitivity of 0.50 and specificity of 0.97.

CONCLUSION

The deep learning system can discriminate malignant diseases for pulmonary nodules measuring no more than 3 cm. The AI model has a high positive predictive value for invasive adenocarcinoma with respect to intraoperative frozen section examination, which might help determine the individualized surgical strategy.

A case report and literature review

Echinococcosis is caused by tapeworms belonging to the Echinococcus genus. The most common site of infection is the liver although it may involve almost any organ. Symptoms of pulmonary echinococcosis vary depending on the location and structure of the cyst. While uncomplicated cysts usually appear at imaging as well-defined homogeneous lesions with fluid content and smooth walls of variable thickness, complicated lesions may have a more heterogeneous content with higher density making more difficult the distinction from malignancies or other infections. Hereby we describe the case of a 61-year-old Northern African male admitted to our tertiary center for left upper chest pain who then underwent a chest computed tomography (CT) scan which demonstrated a large hypodense lesion, with smooth and thick walls, in the upper left lobe. The following magnetic resonance confirmed the homogeneous fluid content, and the 18 F- fluorodeoxyglucose-positron emission tomography/CT demonstrated a mild uptake of the walls. According to these findings, the main differential diagnoses at imaging included bronchogenic cyst, synovial sarcoma, and pulmonary hematoma although the patient denied any recent trauma. Given the large size and clinical symptoms he underwent surgery. Intra-operative frozen section, supported by imprint cytology, excluded the presence of malignancy while suggested an echinococcal laminar exocyst. The final pathological examination confirmed the diagnosis of echinococcosis (i.e., Echinococcus Granulosus protoscolex). After surgery he was treated with albendazole and at the six-month follow-up he was in good clinical conditions. Our case highlights the importance of considering rare infections, particularly in individuals from endemic areas. Frozen tissue analyses can be a diagnostic challenge and often require ancillary tools such as imprint cytology and serial sections for more sensitive and accurate diagnosis.

Selective Mediastinal Lymph Node Dissection Strategy for Clinical T1N0 Invasive Lung Cancer: A Prospective, Multicenter, Clinical Trial

INTRODUCTION

We aimed to prospectively evaluate our previously proposed selective mediastinal lymph node (LN) dissection strategy for peripheral clinical T1N0 invasive NSCLC.

METHODS

This is a multicenter, prospective clinical trial in China. We set six criteria for predicting negative LN stations and finally guiding selective LN dissection. Consolidation tumor ratio less than or equal to 0.5, segment location, lepidic-predominant adenocarcinoma (LPA), negative hilar nodes (stations 10-12), and negative visceral pleural invasion (VPI) were used separately or in combination as predictors of negative LN status in the whole, superior, or inferior mediastinal zone. LPA, hilar node involvement, and VPI were diagnosed intraoperatively. All patients actually underwent systematic mediastinal LN dissection. The primary end point was the accuracy of the strategy in predicting LN involvement. If LN metastasis occurred in certain mediastinal zone that was predicted to be negative, it was considered as an "inaccurate" case.

RESULTS

A total of 720 patients were enrolled. The median number of LN dissected was 15 (interquartile range: 11-20). All negative node status in certain mediastinal zone was correctly predicted by the strategy. Compared with final pathologic findings, the accuracy of frozen section to diagnose LPA, VPI, and hilar node metastasis was 94.0%, 98.9%, and 99.6%, respectively. Inaccurate intraoperative diagnosis of LPA, VPI, or hilar node metastasis did not lead to inaccurate prediction of node-negative status.

CONCLUSIONS

This is the first prospective trial validating the specific mediastinal LN metastasis pattern in cT1N0 invasive NSCLC, which provides important evidence for clinical applications of selective LN dissection strategy.

Frozen Section Analysis in Head and Neck Surgical Pathology: A Narrative Review of the Past, Present, and Future of Intraoperative Pathologic Consultation

Frozen section has remained the diagnostic gold standard for intraoperative pathological evaluation of surgical margins for head and neck specimens. While achieving tumor-free margins is of utmost importance to all head and neck surgeons, in practice, there are numerous debates and a lack of standardization for the role and method of intraoperative pathologic consultation. This review serves as a summary guide to the historical and contemporary practice of frozen section analysis and margin mapping in head and neck cancer. In addition, this review discusses current challenges in head and neck surgical pathology, and introduces 3D scanning as a groundbreaking technology to bypass many of the pitfalls in the current frozen section workflow. The ultimate goal for all head and neck pathologists and surgeons should be to modernize practices and take advantage of new technology, such as virtual 3D specimen mapping techniques, that improves the workflow for intraoperative frozen section analysis.

Diagnostic accuracy of intraoperative margin assessment techniques in surgery for head and neck squamous cell carcinoma: A meta-analysis

BACKGROUND

Positive margins following head and neck squamous cell carcinoma (HNSCC) surgery lead to significant morbidity and mortality. Existing Intraoperative Margin Assessment (IMA) techniques are not widely used due to limitations in sampling technique, time constraints and resource requirements. We performed a meta-analysis of the diagnostic performance of existing IMA techniques in HNSCC, providing a benchmark against which emerging techniques may be judged.

METHODS

The study was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. Studies were included if they reported diagnostic metrics of techniques used during HNSCC surgery, compared with permanent histopathology. Screening, manuscript review and data extraction was performed by multiple independent observers. Pooled sensitivity and specificity were estimated using the bivariate random effects model.

RESULTS

From an initial 2344 references, 35 studies were included for meta-analysis. Sensitivity (Sens), specificity (Spec), diagnostic odds ratio (DOR) and area under the receiver operating characteristic curve (AUROC) were calculated for each group (n, Sens, Spec, DOR, AUROC): frozen section = 13, 0.798, 0.991, 309.8, 0.976; tumour-targeted fluorescence (TTF) = 5, 0.957, 0.827, 66.4, 0.944; optical techniques = 10, 0.919, 0.855, 58.9, 0.925; touch imprint cytology = 3, 0.925, 0.988, 51.1, 0.919; topical staining = 4, 0.918, 0.759, 16.4, 0.833.

CONCLUSIONS

Frozen section and TTF had the best diagnostic performance. Frozen section is limited by sampling error. TTF shows promise but involves administration of a systemic agent. Neither is currently in widespread clinical use. Emerging techniques must demonstrate competitive diagnostic accuracy whilst allowing rapid, reliable, cost-effective results.

Application of lean methodology to frozen section workflow - An audit of present practices at a single large oncology center

AIM

We conducted a pilot study to analyze the frozen section workflow in the histopathology department and to construct a future state map using Lean management for a better efficiency.

METHOD

We analyzed the current state of frozen section workflow in our department, from receipt of the specimen to delivery of slides to the pathologist to communication of report to the surgeon by using value-stream mapping and spaghetti diagram. Further, with the help of the fishbone diagram and Pareto's chart, root cause analysis was done, and a future state map was created with help of a spaghetti diagram to eliminate the non-value-added steps.

RESULTS

Our current value-stream map identified a total specimen processing time of 3393 min of which 2880 min were value-added, translating to a process cycle efficiency of 84.88 %. Also, with the help of tools of lean management we constructed a future state map to improve process cycle efficiency.

CONCLUSION

In this study, we have attempted to use a few tools of lean management systems and suggested ways for continuous improvements that can be successfully implemented in histopathology laboratories.

Diagnostic accuracy of frozen section and patterns of nodal spread in high grade endometrial cancer: A secondary outcome of the SENTOR prospective cohort study

OBJECTIVES

The study aimed to define the accuracy of intraoperative frozen section (FS) for the detection of metastases in sentinel lymph node biopsy (SLNB) and describe the pattern of lymph node (LN) spread and relation to molecular classifiers in patients with high-grade endometrial cancer (EC).

METHODS

We performed a secondary outcome of clinicopathologic data from the Sentinel Lymph Node Biopsy versus Lymphadenectomy for Intermediate- and High-Grade Endometrial Cancer Staging (SENTOR) prospective cohort study evaluating SLNB in patients with clinical stage I high-grade EC (ClinicalTrials.gov ID: NCT01886066). The primary outcome was the sensitivity of FS of the sentinel lymph node (SLN) specimen, compared to a standardized ultrastaging protocol. Secondary outcomes included the pattern and characteristics of LN spread.

RESULTS

There were 126 patients with high-grade EC with a median age of 66 years (range:44-86) and a median Body Mass Index (BMI) of 26.9 kg/m² (range:17.6-49.3). FS was performed on surgical specimens from 212 hemipelves; SLNs were identified in 202 specimens (95.7%) and fatty tissue alone was identified in 10 specimens (4.7%). Of the 202 hemipelves in which SLNs were identified, 24 were positive for metastatic disease on final pathology. Initial FS correctly identified only 12, yielding a sensitivity of 50% (12/24, 95% CI 29.6-70.4) and a negative predictive value of 94% (178/190, 95% CI 89-96.5). A total of 24 patients (19%) had LN metastases: 16 (13%) had isolated pelvic metastases, 7 (6%) had both pelvic and para-aortic metastases and 1 (0.8%) had an isolated para-aortic metastasis.

CONCLUSIONS

Intraoperative FS of SLNs in high-grade EC patients has poor sensitivity. Since isolated para-aortic metastases are rare, para-aortic lymphadenectomy may be omitted in patients in which SLNs were successfully mapped to the pelvis.

Validation of Remote Digital Pathology based diagnostic reporting of Frozen Sections from home

Background

Despite the promising applications of whole-slide imaging (WSI) for frozen section (FS) diagnosis, its adoption for remote reporting is limited.

Objective

To assess the feasibility and performance of home-based remote digital consultation for FS diagnosis.

Material & Method

Cases accessioned beyond regular working hours (5 pm-10 pm) were reported simultaneously using optical microscopy (OM) and WSI. Validation of WSI for FS diagnosis from a remote site, i.e. home, was performed by 5 pathologists. Cases were scanned using a portable scanner (Grundium Ocus®40) and previewed on consumer-grade computer devices through a web-based browser (http://grundium.net). Clinical data and diagnostic reports were shared through a google spreadsheet. The diagnostic concordance, inter- and intra-observer agreement for FS diagnosis by WSI versus OM, and turnaround time (TAT), were recorded.

Results

The overall diagnostic accuracy for OM and WSI (from home) was 98.2% (range 97%-100%) and 97.6% (range 95%-99%), respectively, when compared with the reference standard. Almost perfect inter-observer (k = 0.993) and intra-observer (k = 0.987) agreement for WSI was observed by 4 pathologists. Pathologists used consumer-grade laptops/desktops with an average screen size of 14.58 inches (range = 12.3-17.7 inches) and a network speed of 64 megabits per second (range: 10-90 Mbps). The mean diagnostic assessment time per case for OM and WSI was 1:48 min and 5:54 min, respectively. Mean TAT of 27.27 min per case was observed using WSI from home. Seamless connectivity was observed in approximately 75% of cases.

Conclusion

This study validates the role of WSI for remote FS diagnosis for its safe and efficient adoption in clinical use.

Use and Accuracy of Intraoperative Frozen Section Analysis for Ovarian Masses in Children and Adolescents

STUDY OBJECTIVE

Describe the current practice patterns and diagnostic accuracy of frozen section (FS) pathology for children and adolescents with ovarian masses DESIGN: Prospective cohort study from 2018 to 2021 SETTING: Eleven children's hospitals PARTICIPANTS: Females age 6-21 years undergoing surgical management of an ovarian mass INTERVENTIONS: Obtaining intraoperative FS pathology MAIN OUTCOME MEASURE: Diagnostic accuracy of FS pathology RESULTS: Of 691 patients who underwent surgical management of an ovarian mass, FS was performed in 27 (3.9%), of which 9 (33.3%) had a final malignant pathology. Among FS patients, 12 of 27 (44.4%) underwent ovary-sparing surgery, and 15 of 27 (55.5%) underwent oophorectomy with or without other procedures. FS results were disparate from final pathology in 7 of 27 (25.9%) cases. FS had a sensitivity of 44.4% and specificity of 94.4% for identifying malignancy, with a c-statistic of 0.69. Malignant diagnoses missed on FS included serous borderline tumor (n = 1), mucinous borderline tumor (n = 2), mucinous carcinoma (n = 1), and immature teratoma (n = 1). FS did not guide intervention in 10 of 27 (37.0%) patients: 9 with benign FS underwent oophorectomy, and 1 with malignant FS did not undergo oophorectomy. Of the 9 patients who underwent oophorectomy with benign FS, 5 (55.6%) had benign and 4 (44.4%) had malignant final pathology.

CONCLUSIONS

FSs are infrequently utilized for pediatric and adolescent ovarian masses and could be inaccurate for predicting malignancy and guiding operative decision-making. We recommend continued assessment and refinement of guidance before any standardization of use of FS to assist with intraoperative decision-making for surgical resection and staging in children and adolescents with ovarian masses.

A rare location of papillary carcinoma: Thyroglossal duct cyst

The inadequate closure of the thyroglossal tract paves the way for a thyroglossal cyst. Thyroglossal duct cyst (TDC) malignancy is quite rare. A thirty-nineyear-old female patient was admitted to the polyclinic with a complaint of palpable mass in the neck. Findings compatible with TDC were determined in the patient's neck screening and it was considered to be malignant due to irregular margins, apparent vascularization and punctual calcifications. Fine needle aspiration biopsy was unremarkable. TDC was excised by Sistrunk procedure and frozen examination was performed. Total thyroidectomy was performed additionally since the result of the frozen examination was found to be compatible with the primary papillary carcinoma of TDC. If preoperative biopsy does not provide a diagnosis, frozen section study will be beneficial in terms of both providing the early diagnosis and directing the operation strategy during the surgery in clinically or radiologically suspected patients.

To Freeze or Not to Freeze? Recommendations for Intraoperative Examination and Gross Prosection of Thyroid Glands

The use of intraoperative consultation for indeterminate thyroid lesions is not advocated but is still requested by some surgeons. Obscured cytomorphology and nonrepresentative sampling limit the specificity of intraoperative assessment. Formalin fixation of thyroid glands before sectioning also minimizes artifacts introduced by fresh sectioning. Inking of thyroid may vary based on institutional preferences and information desired by clinical teams. Sectioning may occur in the conventional transverse method or the modified transverse vertical method to more thoroughly evaluate the lesion's periphery. Gross examination of thyroid lesions should always consider possible high-grade features, such as necrosis or extrathyroidal extension.

Clinical profiles and intraoperative identification of complex glands in stage I lung adenocarcinoma

OBJECTIVES

This study aimed to investigate the potential of complex glandular patterns (CGP) in lymph node micrometastasis (LNMM) and to determine the clinical beneficiaries in stage I lung adenocarcinoma (LUAD) with CGP. Meanwhile, the feasibility of detecting CGP on frozen section was also evaluated.

METHODS

We retrospectively analysed the clinicopathological characteristics of 848 pathologic-stage I LUADs. A logistic regression model and a Cox proportional-hazards model were conducted to define the risk factors for LNMM and survival respectively. Furthermore, 5 pathologists reviewed frozen sections of 100 LUADs independently.

RESULTS

The logistic regression model indicated that CGP [odds ratio 3.89, 95% confidence interval (CI) 2.46-6.15; P < 0.001] was an independent predictor of the presence of LNMM. Subgroup analysis revealed that CGP-present/LNMM-positive LUAD had the highest risk of both loco-regional and distant recurrence. Moreover, adequate lymphadenectomy [recurrence-free survival: hazard ratio (HR) 0.61, 95% CI 0.40-0.95; P = 0.028; overall survival: HR 0.64, 95% CI 0.41-0.99; P = 0.043] and adjuvant chemotherapy (recurrence-free survival: HR 0.30, 95% CI 0.18-0.52; P < 0.001; overall survival: HR 0.33, 95% CI 0.19-0.57; P < 0.001) brought survival benefits to CGP-present patients, especially to CGP-present/LNMM-positive subgroup. Across the 5 pathologists, sensitivity ranged from 59 to 68% and specificity ranged from 79 to 83%, with moderate diagnostic agreement and high interobserver agreement for detecting CGP on frozen section.

CONCLUSIONS

LNMM was more frequently observed in stage I LUAD with CGP. Adequate lymphadenectomy and adjuvant chemotherapy were associated with improved survival in CGP-present patients, especially in CGP-present/LNMM-positive subgroup. Additionally, it is feasible to identify CGP on frozen section intraoperatively.

Preoperative, Intraoperative, and Postoperative Parathyroid Pathology: Clinical Pathologic Collaboration for Optimal Patient Management

Parathyroid disease typically presents with parathyroid hyperfunction as result of neoplasia or a consequence of non-neoplastic systemic disease. Given the parathyroid gland is a hormonally active organ with broad physiologic implications and serologically accessible markers for monitoring, the diagnosis of parathyroid disease is predominantly a clinical pathologic correlation. We provide the current pathological correlates of parathyroid disease and discuss preoperative, intraoperative, and postoperative pathology consultative practice for optimal patient care.

Frozen sections accurately predict the IASLC proposed grading system and prognosis in patients with invasive lung adenocarcinomas

INTRODUCTION

The International Association for the Study of Lung Cancer (IASLC) newly proposed grading system for lung adenocarcinomas (ADC) has been shown to be of prognostic significance. Hence, intraoperative consultation for the grading system was important regarding the surgical decision-making. Here, we evaluated the accuracy and interobserver agreement for IASLC grading system on frozen section (FS), and further investigated the prognostic performance.

METHODS

FS and final pathology (FP) slides were reviewed by three pathologists for tumor grading in 373 stage I lung ADC following surgical resection from January to June 2013 (retrospective cohort). A prospective multicenter cohort (January to June 2021, n = 212) were included to confirm the results.

RESULTS

The overall concordance rates between FS and FP were 79.1% (κ = 0.650) and 89.6% (κ = 0.729) with substantial agreement in retrospective and prospective cohorts, respectively. Presence of complex gland was the only independent predictor of discrepancy between FS and FP (presence versus. absence: odds ratio, 2.193; P = 0.015). The interobserver agreement for IASLC grading system on FS among three pathologists were satisfactory (κ = 0.672 for retrospective cohort; κ = 0.752 for prospective cohort). Moreover, the IASLC grading system by FS diagnosis could well predict recurrence-free survival and overall survival for patients with stage I invasive lung ADC.

CONCLUSIONS

Our results suggest that FS had high diagnostic accuracy and satisfactory interobserver agreement for IASLC grading system. Future prospective studies are merited to validate the feasibility of using FS to match patients into appropriate surgical type.

Validation and implementation of Aperio LV1 remote live view telepathology system for intraoperative frozen section diagnosis

Introduction

Telepathology (TP) allows for remote slide review with performance comparable to traditional light microscopy. Use of TP in the intraoperative setting allows for faster turnaround and greater user convenience by obviating the physical presence of the attending pathologist. We sought to perform a practical validation of an intraoperative TP system using the Leica Aperio LV1 scanner in tandem with Zoom teleconferencing software.

Methods

A validation was performed in accordance with recommendations from CAP/ASCP, using a retrospectively identified sample of surgical pathology cases with a 1 year washout period. Only cases with frozen-final concordance were included. Validators underwent training in the operation of the instrument and conferencing interface, then reviewed the blinded slide set annotated with clinical information. Validator diagnoses were compared to original diagnoses for concordance.

Results

60 slides were chosen for inclusion. 8 validators completed the slide review, each requiring 2 h. The validation was completed in 2 weeks. Overall concordance was 96.4%. Intraobserver concordance was 97.3%. No major technical hurdles were encountered.

Conclusion

Validation of the intraoperative TP system was completed rapidly and with high concordance, comparable to traditional light microscopy. Institutional teleconferencing implementation driven by the COVID pandemic facilitated ease of adoption.

The NeuroSAFE frozen section technique during radical prostatectomy - Implementation and optimization of technical aspects in a routine pathology workflow

BACKGROUND AND AIMS

In prostate cancer patients, application of the NeuroSAFE frozen section technique during radical prostatectomy has been shown to increase the rate of nerve sparing surgery and to improve functional outcome for the patients. The aim of this study is to report on technical and organizational optimization opportunities of the procedure.

MATERIAL AND METHODS

All patients submitted to bilateral intraoperative frozen section from January 2018 until December 2020 (n = 452) were retrospectively analyzed and parameters such as turnaround time, staff situation in the laboratory and histologic properties of the tumors were assessed.

RESULTS

The median turnaround time per case was 40.3 ( ± 10.5) min. In 2020 the average time needed from accessioning to diagnosis was 38.1 min. Multivariate linear regression suggested that the number of technical assistants/cryotomes (46.1 min vs. 39.13 min; p < 0.001), the place of microscopic examination (43.0 min vs. 38.7 min; p < 0.001) and the presence of a positive margin (38.0 vs. 44.0 min; p < 0.001) were significant influential factors. The turnaround time was independent of the uropathological expertize of the consultant (39.84 min vs. 40.7 min; p = 0.09), the tumor grade (42.3 vs 39.8 min; p = 0.493) and the presence of extraprostatic extension (44.0 vs 39.8 min; p = 0.099).

CONCLUSION

The implementation of simple optimization measures in the workflow as well as structured training of all pathology staff involved in the examination leads to a significant increase in the efficiency of the examination while maintaining the same level of resources. The results could thus be a contribution to the broader application of the procedure.

Assessment of Quality of Frozen Section Services at a Large Academic Hospital Before and After Relocation

OBJECTIVES

To determine outcomes following relocation of frozen section services (FSS) and the implementation of a dedicated gastrointestinal frozen service.

METHODS

We reviewed our FSS 6 months prior to and following FSS relocation. Satisfaction surveys were sent to surgeons and pathologists. Survey feedback resulted in a pilot of gastrointestinal subspecialist frozen section coverage.

RESULTS

There were 1,607 and 1,472 specimens from 667 and 602 patients pre- and post-FSS relocation, respectively. There was a decline in median specimen delivery time to pathology (12 vs 10 minutes, P < .001) and an increase in median time from receipt in pathology to intraoperative diagnosis (20 vs 22 minutes, P = .008) in cases with intrapathology consultation but no change without consultation (median, 19 minutes). Intrapathology consultation decreased from 19.7% (317/1,607) to 11.5% (169/1,472) (P < .001). Discordance rates between frozen section and permanent section remained low and similar (2.0% [33/1,607] vs 2.7% [40/1,472], P = .24). There was no significant change in discordance with dedicated gastrointestinal subspecialty frozen section interpretation.

CONCLUSIONS

Relocation of FSS and dedicated subspecialty interpretation may improve surgeon satisfaction but can also create workflow challenges. Pathology departments need to achieve a balance between satisfaction and adequacy to establish best frozen section coverage models.

A retrospective analysis of the diagnostic accuracy and technical quality of frozen sections in detecting hepatobiliary lesions

INTRODUCTION

Pathological consultation on intraoperative frozen sections plays a crucial role in the management of patients undergoing surgical therapy, and is also a key indicator for quality assurance in anatomical pathology. This study aimed to evaluate the diagnostic accuracy and technical quality of frozen sections in detecting hepatobiliary lesions with malignant potential.

PATIENTS AND METHODS

A retrospective database review was performed for 1208 cases intraoperative pathology consultation who underwent hepatobiliary lesions resection at our institution from 2016 to 2020. The intraoperative consultation cases during a 5-year period were reviewed and analyzed, including the measurement of the diagnostic accuracy and turnaround time of frozen sections, the reasons for discrepancies, and the rates of discordance and deferral.

RESULTS

In this study, we confirmed that the overall accuracy, sensitivity and specificity were 95.3 %, 96.3 % and 96.6 %, respectively, in distinguishing benign from malignant lesions. The rates of deferred and discordant diagnoses were 2.57 % and 2.2 %, respectively. The overall frozen section turnaround time was 22.1 min. The most common cause of deferred and discordant was poor section quality, the lesion of bile duct margin on the frozen section, misinterpretation of difficult and complicated cases, etc. CONCLUSIONS: This study confirms that the intraoperative frozen sections can serve as a rapid, accurate and robust method for the pathological diagnosis of suspected hepatobiliary lesions. However, it should be noted that some poor technical problems, pathological assessment of tumor margin and difficult cases are the most frequently causes of deferred and discordant interpretations.

Utility of frozen section in pediatric and adolescent malignant ovarian nonseminomatous germ cell tumors: A report from the children's oncology group

PURPOSE

In adult women, most malignant ovarian tumors are epithelial in origin. The use of intra-operative frozen section to distinguish between benign and malignant histology is reliable in guiding operative decision-making to determine the extent of surgical staging required. Pediatric and adolescent patients with ovarian masses have a much different spectrum of pathology with most tumors arising from germ cell precursors. This review was undertaken to assess the concordance between the intra-operative frozen section and the final diagnosis as an aid to guide extent of surgical staging in a group of pediatric and adolescent patients with malignant ovarian germ cell tumors.

METHODS

Records of patients aged 0 to 20 years with malignant ovarian germ cell tumors enrolled on Children's Oncology Group study AGCT0132 were reviewed. Pathology reports from patients who had both intra-operative frozen section diagnosis and final paraffin section diagnosis were compared using descriptive statistics. By inclusion criteria for the study, all patients had a final diagnosis of malignancy with required yolk sac tumor, choriocarcinoma or embryonal carcinoma histology. Available central review of pathology final paraffin section slides were compared with final institution pathology reports.

RESULTS

Of 131 eligible patients with ovarian germ cell tumors, 60 (45.8%) had both intra-operative frozen section and final paraffin section diagnoses available. Intra-operative frozen section diagnoses were classified as: incorrect diagnosis of benign tumor (13.3%), confirmation of malignancy (61.7%), immature teratoma (16.7%), germ cell tumor not otherwise specified (5%) and no diagnosis provided (3.3%). Intra-operative frozen section was incorrect in 23 of 60 (38.3%) patients evaluated. Central pathology review was concordant with the final institution pathology diagnosis in 76.3% of patients. Central pathology review identified additional germ cell tumor components in 23.7% of patients.

CONCLUSIONS

In pediatric and adolescent patients with a confirmed final diagnosis of ovarian germ cell malignancy, intra-operative frozen section diagnosis is not reliable to inform the extent of surgical staging required. Central review by an expert germ cell tumor pathologist provides important additional information to guide therapy.

NeuroSAFE PROOF: study protocol for a single-blinded, IDEAL stage 3, multi-centre, randomised controlled trial of NeuroSAFE robotic-assisted radical prostatectomy versus standard robotic-assisted radical prostatectomy in men with localized prostate cancer

BACKGROUND

Robotic radical prostatectomy (RARP) is a first-line curative treatment option for localized prostate cancer. Postoperative erectile dysfunction and urinary incontinence are common associated adverse side effects that can negatively impact patients' quality of life. Preserving the lateral neurovascular bundles (NS) during RARP improves functional outcomes. However, selecting men for NS may be difficult when there is concern about incurring in positive surgical margin (PSM) which in turn risks adverse oncological outcomes. The NeuroSAFE technique (intra-operative frozen section examination of the neurovascular structure adjacent prostate margin) can provide real-time pathological consult to promote optimal NS whilst avoiding PSM.

METHODS

NeuroSAFE PROOF is a single-blinded, multi-centre, randomised controlled trial (RCT) in which men are randomly allocated 1:1 to either NeuroSAFE RARP or standard RARP. Men electing for RARP as primary treatment, who are continent and have good baseline erectile function (EF), defined by International Index of Erectile Function (IIEF-5) score > 21, are eligible. NS in the intervention arm is guided by the NeuroSAFE technique. NS in the standard arm is based on standard of care, i.e. a pre-operative image-based planning meeting, patient-specific clinical information, and digital rectal examination. The primary outcome is assessment of EF at 12 months. The primary endpoint is the proportion of men who achieve IIEF-5 score ≥ 21. A sample size of 404 was calculated to give a power of 90% to detect a difference of 14% between groups based on a feasibility study. Oncological outcomes are continuously monitored by an independent Data Monitoring Committee. Key secondary outcomes include urinary continence at 3 months assessed by the international consultation on incontinence questionnaire, rate of biochemical recurrence, EF recovery at 24 months, and difference in quality of life.

DISCUSSION

NeuroSAFE PROOF is the first RCT of intra-operative frozen section during radical prostatectomy in the world. It is properly powered to evaluate a difference in the recovery of EF for men undergoing RARP assessed by patient-reported outcome measures. It will provide evidence to guide the use of the NeuroSAFE technique around the world.

TRIAL REGISTRATION

NCT03317990 (23 October 2017). Regional Ethics Committee; reference 17/LO/1978.

Pathological processing of sentinel lymph nodes in endometrial carcinoma - routine aspects of grossing, ultra-staging, and surgico-pathological parameters in a series of 833 lymph nodes

Sentinel lymph nodes are widely accepted in the treatment of endometrial carcinoma. Whereas surgical aspects are well studied, the pathological work-up in terms of grossing, frozen section, and the so-called ultra-staging is still a matter of debate. This results in conflicting national or center-based recommendations. In a series of consecutive 833 sentinel lymph nodes from 206 patients in endometrial carcinomas, we compared three different grossing techniques and the use of frozen section in terms of anatomy, detection rates, and survival. In total, 42 macro-metastases, 6 micro-metastases, and 25 nodes with isolated tumor cells were found. Lymph nodes affected at least with micro-metastasis were about 0.5cm enlarged. Detection rates in lamellation technique increased with a step of 5.9% to 8.3% in comparison to bi-valved or complete embedding. The lamellation technique presented with a slight beneficial prognosis in pN0 subgroup (OS, p=0.05), which besides size effects might be attributed to trimming loss. In frozen section, this effect was less pronounced than expected (OS, p=0.56). Ultra-staging only revealed additional micro-metastases and isolated tumor cells. Exclusively, macro-metastases showed poor survival (p<0.001). In multivariate analysis, T-stage, subtype, and lympho-vascular invasion status outperformed this staging parameter significantly. Grossing of sentinel lymph nodes is the most essential step with evidence to prefer lamellation in 2 mm steps. Step sectioning should consider widely spaced protocols to exclude macro-metastases. Frozen sections might add value to the intra-operative assessment of endometrial carcinoma in selected cases. The excellent biological behavior of cases with isolated tumor cells might question the routine application of pan-cytokeratin as ultra-staging method.